REDMOND, Wash., July 17, 2026 /PRNewswire/ — SystImmune Inc. (SystImmune) today announced that its parent company, Sichuan Biokin Pharmaceutical Co., Ltd. (Biokin), has received regulatory approval from China’s National Medical Products Administration (NMPA) for iza-bren (izalontamab brengitecan) for the treatment of adult patients with recurrent or metastatic esophageal squamous cell carcinoma (ESCC) whose disease has progressed following prior platinum-based chemotherapy and PD-1/PD-L1 inhibitor therapy.

This marks the second approved indication for iza-bren in China following its recent approval for recurrent or metastatic nasopharyngeal carcinoma (NPC), further establishing iza-bren as a first-in-class EGFR × HER3 bispecific antibody-drug conjugate (ADC) with broad clinical potential across multiple solid tumors.

The approval is supported by results from the pivotal PANKU-Esophagus01 (BL-B01D1-305) study. The study met both dual primary endpoints of progression-free survival (PFS) and overall survival (OS), demonstrating statistically significant and clinically meaningful improvements versus chemotherapy, while maintaining a manageable safety profile. The results were previously presented during an oral presentation at the 2026 American Society of Clinical Oncology (ASCO) Annual Meeting.

Key results from the PANKU-Esophagus01 study included:

• Median overall survival of 9.8 months with iza-bren versus 7.2 months with chemotherapy (HR=0.64, 95% CI: 0.49–0.83; p=0.0004).
• Median progression-free survival by BICR of 4.2 months with iza-bren versus 2.0 months with chemotherapy (HR:0.50; 95% CI: 0.40-0.63; p<0.0001).
• Low treatment discontinuation due to treatment-related adverse events (2.0%), with a safety profile consistent with previous studies.
• The rates of all grade and grade 3 or higher ILD were low in the iza-bren arm (1.6% / 0.8%) and chemotherapy arm (0.4% / 0%).

“Today’s approval represents another important milestone for iza-bren and validates the potential of our EGFR × HER3 bispecific ADC platform to address significant unmet needs across multiple difficult-to-treat cancers,” said Dr. Yi Zhu, Chairman and Chief Executive Officer of Biokin.  “Following the first global approval ofiIza-bren in nasopharyngeal carcinoma, this second approval in esophageal squamous cell carcinoma further demonstrates the meaningful clinical benefit this medicine can provide to patients.  We are grateful to the patients, investigators, healthcare professionals, and regulatory authorities whose contributions made this achievement possible.”

“Patients with recurrent or metastatic ESCC who progress after first-line therapy have historically faced limited treatment options and poor clinical outcomes,” said Dr. Jonathan Cheng, Chief Medical Officer of SystImmune.  “The BL-B01D1-305 study demonstrated significant improvements in both progression-free and overall survival compared to chemotherapy, supporting iza-bren as a new treatment option for these patients.  We look forward to continuing the global development of iza-bren across a wide range of tumor types.”

Iza-bren is currently being evaluated in multiple global clinical studies across several solid tumor indications, including non-small cell lung cancer, breast cancer, urothelial cancer, and other EGFR/HER3-expressing malignancies.

About PANKU-Esophagus01
PANKU-Esophagus01 (BL-B01D1-305) is a randomized, open-label, multicenter phase 3 clinical trial evaluating iza-bren versus investigator’s choice chemotherapy in patients with recurrent or metastatic esophageal squamous cell carcinoma who experienced disease progression following platinum-based chemotherapy plus PD-1/PD-L1 inhibitor therapy.  A total of 497 patients were randomized across 80 study centers in China.  The study met both dual primary endpoints of progression-free survival and overall survival at the pre-specified interim analysis.  For more detailed information, please visit clinicaltrials.gov (NCT06304974).

About Esophageal Squamous Cell Carcinoma (ESCC)
Esophageal cancer is the seventh most commonly diagnosed cancer and the sixth leading cause of cancer-related death worldwide. Esophageal squamous cell carcinoma (ESCC) is the predominant histologic subtype globally and accounts for approximately 90% of esophageal cancer cases in China. Despite advances in first-line treatment with platinum-based chemotherapy combined with PD-1/PD-L1 inhibitors, most patients with recurrent or metastatic ESCC ultimately experience disease progression and have historically faced limited treatment options in the second-line setting, with poor response rates and a median overall survival of less than one year. New therapies that improve survival while maintaining a manageable safety profile remain a significant unmet medical need for patients with advanced ESCC.

About iza-bren
SystImmune, in collaboration with BMS outside of China, is developing iza-bren (BL-B01D1), a bispecific antibody-drug conjugate (ADC) that targets both EGFR and HER3, which are highly expressed in various epithelial cancers and are known to be associated with cancer cell proliferation and survival. Iza-bren’s dual mechanism of action blocks EGFR and HER3 signals to cancer cells, reducing proliferation and survival signals. In addition, upon antibody mediated internalization, iza-bren’s therapeutic novel Topo1i payload is released causing cytotoxic stress that leads to cancer cell death.

About SystImmune
SystImmune is a clinical-stage biopharmaceutical company located in Redmond, WA. It specializes in developing innovative cancer treatments using its established drug development platforms, focusing on bi-specific, multi-specific antibodies, and antibody-drug conjugates (ADCs). SystImmune has several assets in various stages of clinical trials for solid tumor and hematologic indications. Alongside ongoing clinical trials, SystImmune has a robust preclinical pipeline of potential cancer therapeutics in the discovery or IND-enabling stages, representing cutting-edge biologics development.

Forward-Looking Statements
This press release contains forward-looking statements, including statements regarding the potential clinical benefits of iza-bren, the timing and outcomes of regulatory interactions, and the future development and commercialization of iza-bren. Forward-looking statements are subject to risks and uncertainties that may cause actual results to differ materially. SystImmune undertakes no obligation to update any forward-looking statements contained herein, except as required by law.

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SOURCE SystImmune, Inc.